code: def atts_half():
      return {"a": np.array([-1, 1, 1]), "b": np.array([0, 0, 2])}
  
imports: import pytest
  from pytest_lazyfixture import lazy_fixture
  from quantus.functions.loss_func import mse
  from quantus.functions.similarity_func import *
label_desc: Use image node_id 1 for calling a global function with example usage: atts_half() and returns: dict